This case study aims to discover how journal writing promotes critical reflectivity over time. Six non-native pre-service teachers of English as a Second Language (TESL) in an undergraduate program in Hong Kong took part in a 12-month study from the time they took Internship, which entailed a 2-week placement, to the time they completed Practice Teaching, which entailed a 3-week placement. Before the commencement of the Internship program and after the completion of the Practice Teaching course, the teachers were assigned to write about successful English teachers, understanding and expectations of teaching English in the context of local secondary schools. During the five weeks of teaching practicum, the teachers made daily journal entries freely on any topics they wanted. All entries were coded for topics and reflective traits, and further analyzed for changes in content. Results show that while most reflective traits in the free journal entries were located in the area of evaluating teaching, those in the assigned entries concentrated on theories of teaching. Post-coding interviews were held to allow the teachers to verify the codings and interpretations. Discussion in the interviews cross-validated the findings that the six teachers wrote reflectively and that they became more reflective towards the end of the courses, indicating less simplicity in their understanding of the multitude of issues of teaching. Such findings suggest that journal writing as a coursework assignment in pre-service teacher education program fosters teachers' critical reflectivity over time and promotes understanding of the nature, theories, and praxis of teaching. [Copyright of Reflective Practice is the property of Routledge. Full article may be available at the publisher's website: http://dx.doi.org/10.1080/1462394032000082268]